SCIENTISTS believe this incredible footage could show a mysterious monster lurking beneath one of the deepest lakes in the British Isles.

Jonathan Downes, 50, spotted the “creature” thrashing around in one of the Lakes of Killarney in County Kerry, Ireland, while on holiday last week.

His eerie sighting was in the Upper Lake one of three interlinked lakes that make up the area.

The mystery comes just a few years after bizarre unexplained sonar recordings showing a large body were made in the adjoining Muckross Lake.

Along with his wife and friends who also had cameras, Mr Downes, from Crediton, Devon, managed to capture shapes moving across part of the lake.

Mr Downes, who is director at the Centre for Fortean Zoology, said that he had heard of the sonar reading before visiting the lake, but was “ridiculously” lucky to see anything.

He said: “I was actually there with my wife and a friend on holiday.

“All I knew is what I’ve read and having spent an hour on Thursday night looking down on it.

“What we saw was a thing about nine to 10ft long.

“I’d love to say I saw long necks and humps and things but I didn’t.”

Mr Downes, who studies cryptozoology – which investigates unknown species of animals, described seeing what he see described as appearing to be “a long thin eel-like creature appearing about 10ft long”.

“I believe it must be a large eel,” he said. “It was a pale colour.

“What I saw didn’t actually really come out on the picture as well.”

Pat Foley, deputy regional manager of National Park and Wildlife Service, which oversees Killarney National Park, said that there has been some unusual readings taken about six years ago, which indicated an unknown figure in Muckross Lake.

“I think it was about 2003 there was a survey taken,” he said.

“They were getting some sort of strange picture coming back.

“The image was a large and dark blob which I presume, for economic reasons, was described as a monster.”

The Lakes of Killarney have much in common with Loch Ness – home of the world’s most famous monster – just across the Irish Sea in Scotland.

Both are large very deep lakes with similar fish species including Arctic char.

Loch Ness is the deepest lake in Britain, whilst Muckross Lake measures up to 70m deep, is along with Lough Leane, Ireland’s deepest lake.

At the time of the sonar findings in Muckross Lake in Paddy O’Sullivan, Killarney National Park manager for the National Parks and Wildlife Service said: “I am very excited by these findings and am delighted that the ancient fish community of these lakes are being examined by the Irish Char Conservation Group and scientists from around the world.

“These interesting findings can only be good for Killarney from a public awareness and a tourism point of view.

“Whatever the thing turns out to be it will be afforded our fullest protection under EU law as the Muckross forms part of a Special Area of Conservation.”